Signal-translating devices of the traveling-wave type



Sept. 25, 1956 R. ADLER 2,764,710

SIGNAL-TRANSLATING DEVICES OF THE TRAVELING-WAVE TYPE Filed March 17, 1951 Fig.1

GAIN-b ATTENUATION O ROBERT ADLER J:

IO ATTORIVE United States Patent O SIGNAL-TRANSLATING DEVICES OF THE TRAVELING-WAVE TYPE Application March 17, 1951, Serial No. 216,211

19 Claims. (Cl. SIS-3.6)

This invention relates to signal-translating devices, and more particularly to such devices of the traveling-wave type.

It has been proposed to obtain an exponential increase in the amplitude of a signal Wave traveling along a lowvelocity helical transmission line by directing a concentrated electron beam longitudinally within the line and by so constructing the line that the propagation velocity of the traveling-wave impressed on the line is substantially equal to that of the electron beam. A travelingwave device constructed in accordance with this principle is inherently restricted in its application to ultra-high frequencies greater than about 1,000 megacycles.

In the copending application of Robert Adler, Serial No. 92,437, filed May 10, 1949, for Signal Translating Devices of the Traveling Wave Type, now Patent No. 2,687,494, and assigned to the present assignee, there is disclosed and claimed a new type of traveling-wave exponential amplifier which is particularly adapted for radio-frequency amplification in the range between 100 and 1,000 megacycles. In a preferred embodiment, space electrons from an elongated cathode are projected transversely of a low-velocity transmission line on which a traveling signal wave is impressed. Individual space electrons are first controlled in number by the instantaneous potential distribution developed by a first, or control, portion of the line and subsequently interact with a second, or receptor, portion of the line to produce a signal corresponding to the number of the electrons passing the control portion. The transmission line is biased to a potential near that of the cathode, and an accelerating electrode is interposed between the control and receptor portions of the line, so that the control portion functions as an intensity-control grid and the output signal is induced at the receptor portion by space charge coupling. In order to obtain a direction-sensitive attenuation characteristic to permit stable amplification of a traveling signal wave in a preferred direction along the line, the points of interaction of the space electrons with the control and receptor portions are axially displaced from one another. The space electrons are so directed and timed that the signal produced at the receptor portion reinforces the traveling signal wave in one direction but is in phase opposition with the signal wave when that wave travels in the opposite direction.

With a device of this latter type, stable signal amplification is only obtained for signal waves traveling in the preferred direction throughout a band of frequencies having a maximum width substantially equal to two-thirds of the center frequency for which the tube is designed. At frequencies outside this band, the traveling signal wave is attenuated in either direction, and at very much higher frequencies the direction-sensitive nature of the attenuation characteristic is no longer obtained. Moreover, the electrode configurations and spacings are quite critical and do not lend themselves as readily as desired to mass production techniques. Further, such tubes are inherently adapted to the amplification of a signal originating ice at a single-ended source and are not conveniently adaptable to balanced or push-pull operation.

It is a primary object of the present invention to provide a new and improved signal-translating device of the traveling-wave type which employs the fundamental principle set forth in the above-identified copending application while providing stable amplification over a wider frequency band. I g

It is a further object of the invention to provide an improved deflection-control signal-translating device of the traveling-wave type. 9

Still another object of the invention is to provide a new and improved traveling-wave signal-translating device which is particularly adapted to balanced or pushpull operation. J

A further object of the invention is to provide a new and improved signal-translating device of the general type described in the above-identified copending application in Which the constructional difficulties are alleviated so as to facilitate reproduction on a large scale commercial basis. a

A deflection-control signal-translating device of the traveling-wave type, in accordance with the present invention, comprises means including an elongated cathode for projecting a sheet-like beam of space electrons along a predetermined path. A pair of deflection-control electrodes are disposed on opposite sides of that predetermined path for subjecting the electrons to deflection control; at least one of these deflection-control electrodes comprises a control portion of a low-velocity wave-transmission line having an axis substantially parallel with the cathode and substantially perpendicular to the electron beam path. The transmission line has an axial length which is large relative to the effective wavelength of a signal traveling along the line and includes a receptor portion more remote from the cathode than the control portion and electrically intercoupled therewith. The device further includes means for directing the controlled electrons to the receptor portion of the line at individual localized regions of substantially different instantaneous phase of the traveling wave than the respective regions of the control portion of the line where the electrons were subjected to deflection control.

The features of the present invention which are believed to be novel are set forth with particularity in the appended claims. The invention, together with further objects and advantages thereof, may best be understood, however, by reference to the following description taken in connection with the accompanying drawings, in the several figures of which like reference numerals indicate like elements, and in which:

Figures 1 and 2 are cross-sectional views of a new and improved deflection-control signal-translating device constructed in accordance with the present invention, Figure 1 being a cross-section taken along the line 1-1 of Figure 2, and Figure 2 being a cross-section taken along the line 2-2 of Figure 1;

Figure 3 is a graphical representation of an operating characteristic of the device of Figures 1 and 2;

Figures 4 and 5 are cross-sectional views, similar to that of Figure 2, of other embodiments of the invention, and

Figure 6 is a fragmentary cross-sectional view similar to that of Figure 1, of another embodiment of the. invention.

The tube represented in Figures 1 and 2 comprises a thermionic cathode 10 having an elongated electron emissive surface 11 and encompassed by a focusing or beamdirecting electrode 12. Electrons originating at emissive surface 11 and projected through the slot in focusing electrode- 12 are subjected to an accelerating field established by an accelerating electrode 13.: Accelerating mission line.

.and 15, respectively. wound: .oncerarnic forms: 16v and 17, constituting a balanced low-velocitytransmission'line. Conductive helices 14 and15xmay be. constructed by winding wire conductors around ceramic vforms 16 and 17, by employing printed circuit techniques; or in any other suitablemanner known in the art. As :bestv seen in .Figure 2, helical conductors 14 and15 are eachlongitudinally recessed at 18 and 19 respectively; the configuration of the longitudinal recesses isnot critical and may be adapted to facilitate the particular process employed in fabricating conductive helices 14 and '15. A suppressor electrode 20 is disposed between helical con ductors 14 and 15 in the undeflected path ofthe electron beamprojected through the slot in accelerating electrode 13. The entire structure is symmetrical with respect tov a center plane, represented by'the line 1-1 of Figure .2,v and is enclosed Within :an evacuated envelope (not shown); A pair of external coils 21. and 22' are provided forthepurpose of producing a transverse magnetic'field', represented by the arrows H, within the device to deflect the space electrons longitudinally of the trans- Eachof-the conductive'helices 14 and 15 is provided with an input-terminal and an output. terminal, the input and output terminals 23 and 24 of conductive helix 15 beingshown in Figure 1.

In operation, a balanced input signal is applied be tween the input terminals of conductive helices 14 and 15. Space electrons emerging'from the slot in accelerating electrode 13 are first projected between opposed portions 25 and 26 of helices 14 and 15 respectively. Opposed portions 25 and 26 constitute a control portion of the balanced low-velocity transmission line comprised of conductive helices 14 and 15. As the space electrons are projected adjacent the control portion'25, 26 of the line, they are subjected to deflection-control-in accordance with, the instantaneous potential distribution developed by the traveling signalwave. After being subjected to deflection-control, the space electrons are directed to opposedzportions 27' and 28 of-helices 14 and 15 which constitute a receptor portion of the balanced transmission line. Helices 14 and..15 are maintained at a positive unidirectional operating potential by connection to a suitable source. (not shown), and suppressor electrode 20 is maintained at or near the potential of cathode to assist in directing the space electrons to thereceptor portion 27, 28 of the balanced line. Individual space electron trajectories 30iare schematically illustrated to facilitate an understanding of the. operation of the invention.

the transmission line is equal to the efiective propagation velocity of the signal wave along the line; the traveling signal wave undergoes an exponential increase in amplitude as it travels along the line.

The operation of the device in Figures 1 and 2 may perhaps best be understood from the following considerations. For an input signal of extremely low frequency, the. electron transittime becomes negligible and-the longitudinal electrondeflection also becomes negligible with respect to the effective wavelength .of the traveling signal wave. Under these conditions, thesignalproduced at receptor portion 27, 28 is 180 degrees out of phase with the traveling signal wave .so .that the. device produces attenuation. This 180-degree phase difference between the output signal induced by the collected space electrons and the traveling input signal wave is caused by phase reversal as in any amplifier tube employing a positive output electrode.

If a balancedhigh-frequency input signal istapplied'bctween terminal 24 of conductive helix 15 and the corresponding terminal of conductive helix-14,Kresulting in a signal wave traveling from Iefttorightiin'Figure .1, the device also exhibits attenuation, since theetfective phase shift which the longitudinallelectron deflection produces between the signal induced at the receptor portion 27,28

- one-fourth cycle and the longitudinalelectron deflection In order'to provide longitudinal displacement 'of the and receptor 27, 28 and the unidirectional. operatingv potentials applied toconductive helices .14 and.15 are selected to provide an electron transit angle, measured from control portion 25, 26 to receptor portion 27, 28, of degrees or one-fourth cycle at the signal frequency. The magnetic field intensity H is adjusted to provide a longitudinal electron deflection of substantially onerfourth of the effective wavelength of the signal wave traveling along the line;'in a practical embodimentthe required I magnetic field intensity may befrom 50 to gauss. Then, in the space between control portion 25, 26 and receptor portion 27, 28, the average electron-velocity I component inthe direction-of'wave propagation-along is one-fourth of the; efiective Wavelength of the traveling signal wave. Nowyif the direction of propagation of the signal wave iszreversed-byapplying the. balanced input signal between terminal. 23. of conductive helix 15 and the corresponding: terminal ofconductive helix 14, the device produces gain: because theetfectivephase shift caused-by .the.longitudinal-electron deflection adds to the phase-shift attributable to electron transit time producing atotalof -'degreesor:one-half cycle of additional phase shift.

Thuslthe' induced output signal reinforces the traveling input signalzwave, and exponential amplitude increaseis obtained.

For convenience, the direction of-signal-wavepropagation for-signal reinforcement is'termed the-forward direction, and is from right to left in Figures 1 and 6. Similarly, the direction of signal wave propagation for signal attenuation is termed the reverse direction.

Figure 3 is a graphical representation of a typical attenuation characteristic obtainable with a device constructed in accordance with Figures 1 and'2 for a particular adjustment of=operating potentials and magnetic field intensity. In Figure 3, attenuation is plotted as a-function of signal frequency and of the direction of signal wave propagation. The solid curve-'40 represents theattenuation characteristic for signal propagationin the-forward direction, from terminal 23-to terminal 24in Figure l. The dotted curve 41 represents the attenuation characteristic for a signal wave-traveling-in the reverse direction, from terminal 24 to terminal-23 of Figure l.

1 If the operatingpotentials and themagnetic field intensity are adjusted to provide an "electrontransit angle from the controlportion to thereceptor portionof one quarter cycleand a longitudinal electron deflection of one-quarter of the effective wavelength'ofthe signal wave traveling alongthe line atthe-operating center frequency fo, the attenuation characteristic 41 in the reverse direction'is constant andindependent of frequency, since-the electrontransit time is'always just suflicient to counteract the effective phase shift attributable to the longitudinal deaxis.

potential of cathode l0.

flection. In other-words, the phase shift resulting from the finite speed of wave travel along the line just cancels that caused by the deflection of the electron trajectories. On the other hand, in the forward direction, these two phase shifts are additive. At the operating center frequency, the total additional phase shift is 180 degrees, so that maximum negative attenuation or gain is achieved. Maximum positive attenuation or loss is encountered at zero frequency and at even integral multiples'of the operating center frequency f0, since at these frequencies the total additional phase shift attributable to electron transit time and longitudinal electron deflection is either zero or an integral multiple of a full cycle. As shown in Figure 3, the attenuation characteristic 40 in the forward 7 direction is substantially of the form of a negative cosine function.

From a consideration of the characteristics in Figure 3, it is apparent that the device of Figures 1 and 2 is capable of achieving stable gain for signals traveling in the forward direction at any frequency between the intercepts f1 and f2 of characteristic 40 with the zero-attenuation Since this characteristic is in the form of a negative cosine function, the maximum obtainable bandwidth for negative attenuation or gain, between frequencies f1 and f2, is numerically equal to the operating center frequency. This represents a material improvement in the ratio of bandwidth to center frequency over the arrangements disclosed in the above-identified copending application which utilize the space charge coupling phenomenon to provide part of the required effective phase shift between the control and receptor portions; in those arrangements, the maximum obtainable ratio of bandwidth to center frequency is in the order of 2:3.-

It is an interesting property of traveling-wave signaltranslating devices of the type shown in Figures 1 and 2, as well as of devices of the type shown and described in the above-identified copending application, that the magnetic-field intensity H required for stable amplification is substantially independent of the operating voltages applied to the tube electrodes. It is well known that the electron transit time is inversely proportional to the square root of the beam potential. Moreover, the curvature of the electron trajectories produced by the magnetic-deflection field is inversely proportional to the square root of the beam potential. Since all the other operating parameters of the device of Figure 1, such as the electrode dimensions and spacings and the effective wave-propagation velocity of the transmission line, are fixed for any particular tube construction, it is apparent that the electron transit angle, measured from the control portion to the receptor portion, and the magnitude of the electron deflec tion caused by the magnetic field are each inversely proportional to the square root of the beam potential. Consequently, for any particular tube construction, the magnetic-field intensity H required for optimum operation is substantially independent of the desired frequency range. The operating center frequency f for the maximum gain may be adjusted simply by varying the operating potentials.

In the embodiment of Figure 4, the longitudinal recesses 18 and 19 of Figure 2 are omitted and instead the two conductive helices 14 and 15 constituting the low-velocity transmission line are arranged so that their opposed surfaces diverge slightly in the direction of electron travel. The focusing electrode between emissive surface 11 and accelerating electrode 13 is shown in the form of a pair of wire electrodes 35 and 36 maintained at or near the In all other respects, the embodiment of Figure 4 is identical with that of Figure 2.

The operation of the embodiment of Figure 4 is identical in all material respects to that of the arrangement of Figure 2, although the control portion 25, 26 and the receptor portion 27, 28 of the balanced transmission line are not as readily distinguishable in a physical sense,

,owing to the omission of the longitudinal recesses 18 and 19. However, similar performance may be obtained with the Figure 4 embodiment with the added advantage of increased simplicity in component construction.

In Figure 5 there is shown a crossasectional view of a modification of the embodiment of Figure 4 which is particularly adapted to use with single-ended input and output circuits. The Figure 5 embodiment is similar to that shown in Figure 4 with the exception that conductive helix 15 is replaced by a dummy or plate electrode 38 to provide a symmetrical field in the absence of an input signal on conductive helix 14. The electron gun construction usedin the Figure 5 embodiment is similar to that shown in Figure 2. As in the other embodiments, the operating potentials and the magnetic field intensity H are adjusted to provide an electron transit angle at the operating center frequency, measured from the control portion to the receptor portion, of substantially 90 degrees or onequarter cycle and a longitudinal electron displacement of substantially one-fourth the elfective wavelength of the traveling signal wave.

In each of the embodiments discussed thus far, a direction-sensitive attenuation characteristic is imparted to a low-velocity transmission line by providing a physical deflection of the electron trajectories, as by means of a magnetic field. The embodiment of Figure 6 achieves a direction-sensitive attenuation characteristic without the necessity of employing a transverse magnetic-deflection The embodiment of Figure 6 is identical with that of Figures 1 and 2 with the exception that the conductive helices are obliquely wound and the magnetic field-producing means are omitted. As in the embodiment of Figures l and 2, space electrons originating at emissive surface 11 of cathode 10 are first subjected to deflectioncontrol in accordance with the instantaneous potential distribution developed by the traveling signal wave and are subsequently directed to a different portion of the line to induce a signal corresponding to the direction of the controlled electrons. The direct operating potentials are adjusted to provide an electron transit angle, measured from control portion 25, 26 to receptor portion 27, 28, of substantially degrees or one-fourth cycle at the frequency of the traveling signal wave. The additional 90- degree effective phase shift required to provide signal reinforcement and to provide a direction-sensitive attenuation characteristic is, however, obtained in a different manner, so that no physical longitudinal deflection of the electron trajectories 30 is required. The necessary effective displacement between the region of interaction of the space electrons with receptor portion 27, 28 and the region of interaction of those same electrons with control portion 25, 26 is provided by winding conductive helices 14 and 15 obliquely with respect to the longitudinal axis. The angle of obliquity is so chosen that transversely aligned points on control portion 25, 26 and receptor portion 27, 28 represent an effective displacement with respect to the traveling signal wave of substantially onefourth of the effective wavelength of the signal wave traveling along the line. In other words, each individual space electron is first projected adjacent the control portion of the line at a particular convolution thereof and is subsequently directed to the receptor portion at a different convolution of the same transmission line without being axially deflected; the effective phase shift introduced in this manner is numerically equal to the instantaneous phase difference between the two convolutions of the line under consideration. For a signal traveling in the forward direction, this effective phase shift is added to that attributable to the electron transit time, and negative attenuation or'gain is achieved. For signals traveling in the reverse direction, the effective phase shift introduced by virtue of the oblique winding of the helices is opposite to that attributable to electron transit time, and positive attenuation or loss is encountered.

In all of the illustrated embodiments, both a focusing crease in the amplitude of a traveling signal wave.

electrode and an accelerating electrode have been-shown between theelectron-emissive' cathode and -the lowvelocitytransmission line. While this electrode arrangement-facilitatesj'the projection of a' well-defined 'focused I beam,- it is possibleto obtain satisfactory results'byomitting one or the other, but not both,-of the focusing electrode and the accelerating-electrode; since'the transmission line is biased at a positive unidirectional operating potential to'permit'the desired deflection-control over-the projected electron beam; arrangements of this latter type may require stricter manufacturing tolerances, but this may be justified by the increased transconductance which maybe'obtainedin-this'manner.

While all the embodiments have been described as being so constructed and arranged that the additional'phase shiftrequired for signal reinforcement is insured by providing an electron transit angleof-one-quarter cycle and a physical displacement between the regions of interaction of the control portion and thereceptor portion of one-quarter'of the effective wavelength of the signal wave traveling along *theline; and while thisarrangement is" desirable to provide a uniform attenuation characteristic independent of frequencyfor signal wavestraveling in the reverse direction, stable gain may be achieved forsome applications by employing difierentelectron transit angles and'physical displacements. For example, the'operating parameters -may be adjusted to provide an electron transit angle of one-eighth cycle at the operating frequency and an'eftective' displacement between the regions of interaction with thecontrol" portion and the receptor portion of threeeights of the effective wavelength'of the signal wave traveling along the line. In general, useful results'may be obtained whenever the total phase shift attributable to electron-transit'time-and effective displacement is substantially 180 degrees at the operating center frequency.

be embodied within .an ordinary miniature receiving tube envelope.

\ than in- 'devices co-nstructed in. accordance with the aboveidentified copendingapplication;and since higheroperat- Since the electrode spacings are less critical ing potentials may be employed, stable amplification may be-obtained athigher frequencies, if desired, by scaling downthe-electrodedimensions andspacings in a manner --well known in the art.

best suited to usein balanced or push-pull systems, it may Although theimproved-device-is readily beadapted to single-ended operation. Moreover, adevice constructed in accordance with-the present invention provides an increased ratio of bandwidth to center frequency as compared'vvith traveling-waveamplifier devices-of the type utilizing space charge coupling as described in the above-identified copending application.

While particular embodiments of i the present invention have been shown and described, it is apparent-that various 'changesand modifioations may be made, and it is 'therefore contemplated in the appended claims to cover all such changes and modifications as fall within the true spirit andscope-of the invention.

I claim: 1. .A defiection-control signal-translating device of the 1 traveling-Wave 1 type comprising: means including an welongated cathode for projecting a sheet-like beam ofspace electrons alonga predetermined-path;- a pair of deflection-control electrodes disposed on'opposite sides ofisaid-predetermined path for subjecting said electrons to deflection control, at leastone of said deflection-control-electrodes comprising a control portion of a lowvelocity wave-transmission line having an axis substantially parallelwith said cathode and substantiallyperpendiculanto said velectron-beam-path and having an axial length which is large relative to theeiiective'wavelength ofv a signal..travelingalongsaid .line,--said line :further- 8 having a receptor portion more remote-from said cathode than said control portion and electrically intercoupled therewith; and means for directing said controlled electrons to said receptorportion of said line at'individually localized-regions 'of substantially ditferent instantaneous phase of said traveling wave than the respective regions of said control portion whereat-said electrons were subjected to deflectioncontrol.

2. A deflection-control signal-translating device of the traveling-wave type comprising: means including an elongated cathode for projecting a sheet-like beamof space electrons along a predetermined path; a pair 'of deflection-controlelectrodes disposed on opposite sides of-said predetermined path for subjecting said electrons to deflection control, at least one of said deflection-control electrodes comprising a control portion of a lowvelocityhelical wave-transmission line havingan axis substantially para-llel'with said cathode and substantially perpendicular to said electron-beam path andhaving-an axial length which is-large relative to the efiective wavelengthof a signal traveling along said line, said control portion-comprising similarly oriented parts of each convolutionof said helical line, and said line further having areceptorportion-more remote from said cathode than said control portion and comprising other similarly oriented parts ofeach convolution of said helical line;

and means for directing said controlled electrons to said receptor portion of said line at individually localized regions of substantially different instantaneous phase of said traveling wave than the respective regions of said control portion Whereat said electrons were subjected to deflection control.

3. A deflection-control signal-translating deviceof the traveling-wave type comprising: means including an elongated cathode for projecting a sheet-like beam of spaceelectrons along a predetermined path; a pair of deflection-control electrodes disposed on opposite sides of said predetermined path for subjecting, said electrons to deflection control, at least one of said deflection-control electrodes comprising a control portion of a lowvelocity obliquely wound helical wave-transmission line having an-axis substantially parallel with said cathode and substantially perpendicular to said electron-beam path and having an axial length which is large relative to the effective wavelength of a signal-traveling along said line,

saidcontrol portion comprising similarly oriented parts of each convolution-of said helical line, and said .line further having a receptor portion more remote from said cathode than said control portion and comprising other similarly'oriented parts of each'convolution of said helical line,'the-angle of obliquity of said line being selected to provide aneffective displacement of approximately onefourth wavelength between transversely aligned parts of said control and receptor portions; and means for directing said controlled electrons to said receptor portion of saidline at individually localized regions in substantial transverse alignment with the respective regions-of said control portion whereat said electrons were subjected to deflection control.

4. -Adeflection-control signal-translating device of the traveling-wave type comprising: 'means including an *elongated'cathode for projecting a sheet-like beam of relative to the effective wavelength of a signal traveling along said'line', said line further having a receptor portion more remote from said cathode than, and on the opposite sideofsaid recess from, said control portion;

and means for directing said controlled-electrons to said receptor portion of said line at individually localized regions of substantially difierent instantaneous phase of said traveling wave than the respective regions of said control portion whereatsaid electrons were subjected to deflection control.

5. A deflection-control signal-translating device of the traveling-wave type comprising: means including an elongated cathode for projecting a sheet-like beam of space electrons along a predetermined path; a pair of deflection-control electrodes disposed on opposite sides of said predeterminedpath for subjecting said electrons to deflection control, at least one of said deflection-control electrodes comprising a control portion of a lowvelocity helical wave-transmission line having an axis substantially parallel with said cathode and substantially perpendicular to said electron-beam path and having an axial length which is large relative to the efiective wavelength of a signal traveling along said line, said control portion comprising similarly oriented parts of each con-a volution of said helical line, and said line further having a receptor portion more remote from said cathode than said control portion and comprising other similarly oriented parts of each convolution of said helical line;

and means for directing each incremental element of.

space electron current to said receptor portion of said line at a diflerent convolution of said line from that at which it was subjected to deflection control.

6. A deflection-control signal-translating device of the traveling-wave type comprising: means including an perpendicular to said electron-beam path and having an axial length which is large relative to the eflective wavelength of a signal traveling along said line, said line further having a receptor portion more remote from said cathode than said control portion and electrically intercoupled therewith; and means for directing said controlled electrons to said receptor portion of said line at individually localized regions of substantially diflEerent instantaneous phase of said traveling wave than the respective regions of said control portion whereat said electrons were subjected to deflection control.

7. A deflection-control signal translating device of the traveling-Wave type comprising: means including an elongated cathode and an accelerating electrode for projecting a sheet-like beam of space electrons along a predetermined path; a pair of deflection-control electrodes disposed on opposite sides of said predetermined path for subjecting said electrons to deflection control, at least one of said deflection-control electrodes comprising a control portion of a low-velocity wave-transmission line having an axis substantially parallel with said cathode and substantially perpendicular to said electron-beam path and having an axial length which is large relative to the efiective wavelength of a signal traveling along said line, said line further having a receptor portion more remote from said cathode than said control portion and electrically inter-coupled therewith; and means for directing said controlled electrons to said receptor portion of said line at individually localized regions of substantially different instantaneous phase of said traveling wave than the respective regions of said control portion whereat said electrons were subjected to deflect-ion control.

8. A deflection-control signal-translating device of the traveling-wave type comprising: means including an elongated cathode and a focusing electrode for projecting a sheet-like beam of space electrons along a predetermined path; a pair of. deflection-control electrodes disposed ca opposite sides of said predetermined path for subjecting said electrons to deflection control, at least one of said deflection-control electrodes comprising-a control portion of a low-velocity wave-transmission line having an axis substantially parallel with said cathode and substantially perpendicular to said electron-beampath and having an axial length which is large relative to the effective wavelength of a signal traveling along said line, said line further having a receptor portion more remote from said cathode than said control portion, and electrically intercoupled therewith; and means for directing said controlled electrons to said receptor portion of said line at individually localized regions of substantially diiferent instantaneous phase of said traveling wave than the respective regions of said control portion whereat said electrons were subjected to deflection control.

9. A deflection-control signal-translating device of the traveling-wave type comprising: means including an elongated cathode, a focusing electrode, and an accelerating electrode for projecting a sheet-like beam of space electrons along a predetermined path; a pair of deflectioncontrol electrodes disposed on opposite sides of said predetermined path for subjecting said electrons to deflection control, at least one of said deflection-control electrodes comprising a control portion of a low-velocity wavetransmission line having an axis substantially parallel with said cathode and substantially perpendicular to said electron-beam path and having an axial length which is large relative to the effective wavelength of a signal traveling along, said line, said line further having a receptor portion more remote from said cathode than said central portion and electrically intercoupled therewith; and means for directing said controlled electrons to said receptor portion of said line at individually localized regions of substantially different instantaneous phase of said traveling wave than the respective regions of said control portion whereat said electrons were subjected to deflection control.

10. A deflection-control signal-translating device of the traveling-wave type comprising: means including an elongated cathode for projecting a sheet-like beam of space electrons along a predetermined path; a pair of deflectioncontrol electrodes disposed on opposite sides of said predetermined path for subjecting said electrons to deflection control, at least one of said deflection-control electrodes comprising a control portion of a low-velocity wave- -transmission line having an axis substantially parallel with said cathode and substantially perpendicular to said electron-beam path and having an axial length which is large relative to the eflective wavelength of a signal traveling along said line, said line further having a receptor portion more remote from said cathode than said control portion and electrically intercoupled therewith; and means including a suppressor electrode for directing said controlled electrons to said receptor portion of said line at individually localized regions of substantially different instantaneous phase of said traveling wave than the respective regions of said control portion whereat said electrons were subjected to deflection control.

11. A deflection-control signal-translating device of the traveling-wave type comprising: means including an elon gated cathode for projecting a sheet-like beam of space electrons along a predetermined path; a pair of deflectioncontrol electrodes disposed on opposite sides of said predetermined path for subjecting said electrons to deflection control, at least one of said deflection-control electrodes comprising a control portion of a low-velocity wavetransmission line having an axis substantially parallel with said cathode and substantially perpendicular to said electron-beam path and having an axial length which is large relative to the efiective wavelength of a signal traveling along said line, said line further having a receptor portion more remote from said cathode than said control portion and electrically intercoupled therewith; and means wave-transmission line having an axis parallel with said cathode and substantiallyperpendicular to said electron-beam path and having an axial length which is large relative tothe efiective wavelength of a ave s-71o *including a suppressonelectrode disposed in said-path in aposition adjacent said receptorportion for directing said "controlled electrons=to said receptorportion of said line atindividually 'loca'liZed regions of substantially'dii'ferent instantaneous phase of said traveling wave than the respective-regions-ofi said control portion whereat said electrons were subjected to deflection control.

12. A-deflection-control signal-translating device of the traveling-wave type comprising: -means including an elongated cathode for projectinga sheet-like beam of space electrons along a predetermined path; a pair of-deflectioncontrol electrodes'disposed on opposite sides of said predetermined path for subjecting said electrons to deflection control, at-leastone of'said deflection-control electrodes comprising a control portion of alow-velocity wave transmission linehaving an axis substantially parallelwith said cathode and substantially perpendicular to said electron 'beam path and having an axial length which is large relative to thceffective wavelength of a signal traveling along said line; said line further having a receptor portion-more remotefrom said cathode than said control "portion and electrically intercoupled therewith; and means for di-rectingsaid controlled electrons'to said receptor portion ot'said line :at-individuallylocalized regions of'su'bstantialphase quadrature of said traveling wave with respect to the respective regions of said control portion whereat-said electrons were subjected to deflection control.

13. A deflection-control signal-translating device of the traveling-wave type comprising: means including an elon-- gated cathode for projecting a sheet-like beam of space electrons along a predetermined path; a pair of deflection- -control electrodesdisposed on opposite sides of said predetermined path for subjecting said electrons to deflection control; at least one of said deflection-control electrodes trons to saidreceptor portion of said line; and means for subjecting said electrons to a transverse magneticfield to deflect said-electrons longitudinally of said line for imparting a direction-sensitive attenuation characteristic to said line.

145A deflection-control signal-translating device of the traveling-wave type comprising: means including an elongated cathode for projecting a sheet-likebeamof space electrons along a predetermined path; a pair of deflection-control electrodes disposed on opposite sides.

of said predetermined path for subjecting said electronsto deflection control each of said deflection-control electrodes comprising a control portion" of a low-velocity substantially signal :traveling along said line, each said line further having a receptor portion more remote from said cathode than said control portion and electricallyintercoupled therewith; andmeans for=directing said controlled electrons to said-receptor portions of said lines at individually localized regions of.-substantially different: instantaneous phase .of said traveling wave than the respective regions ofisaidzcontrol portions whereat said electronswere subjected to deflection control.

- deflection-control "electrodes: :disposed on; opposite sides of saidpredetermined path for subjecting said electrons to deflection control, each of said deflection-control electrodesvcomprising a-control portion of a low-velocity -wave-transmission line having an axis substantially parallel with" said cathode-and substantially perpendicular to said electron-beam path and having an axial length -Which is-large relative to the effective wavelength of a signal travelingalong said line, each said line further having a receptor portion more remote from said cathode than said control portion and electrically intercoupled therewith; and-means including a suppressor electrode interposed in .said path-between said receptor portions fordirecting-said controlled electrons to said receptor portions of said lines at-individually localized regions of -substantially difierent instantaneous phase of said traveling wave than the respective regions-of said control portions whereat said electrons=were subjected to deflection control.

I 16. A defle'ction-control signal-translating device of the traveling-Wave'type comprising: means including an elongated cathode for'projecting a sheet-like beam of space electrons "along a predetermined path; a pair of deflection-control electrodes disposed on opposite sides Ofsaid predeterminedpath for subjecting said electrons *to-deflection control, each of said deflection-control electrodes comprising a .control portion of a low-velocity helicalWave-transmission line having an axis substantially parallel with said cathode and substantially perpendicularto said electron-beam path and having an axial length :which is large relative to-the efiective wavelength of a signalttraveling along said line, each said line further space electrons along a predetermined path; a pair having a receptor portion more remote from said cathode than :said control portion and electrically intercoupled therewith; and means for directing said controlled electrons to said receptor portions of said lines at individually localized regions 'ofsubstan-tially dififerent instantaneous phase of said traveling .wave than the respective regions of said control portions whereat said electrons were subjected to deflection control.

17:. A deflection-control signal-translating device the traveling-wave type" comprising: means including elongated cathode for projecting a sheet-like beam an of of deflection-control electrodes disposed on opposite sides of said predeterminedrpathfor subjecting said electrons to deflection control, veach of said deflection-control electrodes. comprising acontrol portion of a longitudinally recessed low velocity helical wave-transmission line having an axis substantially parallel with said cathode and substantially perpendicular to said electron-beam path and having an axial length which is large relative to the effective Wavelength of a signal traveling along said line, each said line further having a receptor portion more remote from said cathode than, and on the opposite side of said recess from, said control portion; and means for directing said controlled electrons to said receptor portions of. said lines at individually localized regions of substantially differentinstantaneous phase of said travelingwave than therespective regions of said control portions whereat said electrons were subjected to deflection control.

18. A deflection-control signal-translating device of the traveling-wave type comprising: means including an elongated cathode for projecting a sheet-like beam of space electrons along a predetermined path; a pair of delength which is large relative to the effective wavelength of a signal traveling along said line, said line further having-a receptor portion more remote from said cathode 13 than said control portion and electrically intercoupled therewith; means for directing said controlled electrons to said receptor portion of said line; and transverse-magneticfield-producing means for deflecting said electrons longitudinally of said line to impart a direction-sensitive attenuation characteristic to said line.

19. A deflection-control signal-translating device of the traveling-wave type comprising: means including an elongated cathode for projecting a sheet-like beam of space electrons along a predetermined path; a pair of deflection-control electrodes disposed on opposite sides of said predetermined path for subjecting said electrons to deflection control, at least one of said deflection-control electrodes comprising a control portion of a lowvelocity wave-transmission line having an axis substantially parallel with said cathode and substantially perpendicular to said electron-beam path and having an axial length which is large relative to the effective Wavelength of a signal traveling along said line, said line further having a receptor portion more remote from said cathode than said control portion and electrically intercoupled therewith, said control and receptor portions being spaced in the direction of beam travel by a distance corresponding to an electron transit time of substantially one-fourth of a period at the frequency of said traveling wave; and means'for directing said controlled electrons to said receptor portion of said line; and transverse magnetic field producing means for deflecting said electrons longitudinally of said line by a distance of substantially one-fourth of said eifective wavelength to impart a direction-sensitive attenuation characteristic to said line.

References Cited in the file of this patent UNITED STATES PATENTS 2,064,469 Haeff Dec. 15, 1936 2,122,538 Potter July 5, 1938 2,368,031 Llewellyn Jan. 23, 1945 2,414,121 Pierce Jan. 14, 1947 2,511,407 Kleen et al. June 13, 1950 2,535,317 Pierce Dec. 26, 1950 2,566,087 Lerbs Aug. 28, 1951 OTHER REFERENCES Article by Warnecke and Guenard, pp. 259-280, Annales de Radio-electricite, vol. III, No. 14, October 1948. 

